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51.
The pathophysiology of early-stage hip osteoarthritis (EOA) is not fully understood. Although a previous study in an age-unmatched cohort reported that the number of macrophages was increased in knee EOA compared to late OA (LOA), it remained unclear whether increased macrophages in EOA accurately reflect EOA pathology. We investigated the differences in CD14 expression levels between EOA and LOA using age-unmatched and -matched cohorts. Synovial tissues were obtained from 34 EOA (Tönnis grades 0 and 1) and 80 LOA (Tönnis grades 2 and 3) patients. To correct for differences in demographics between patients with LOA and EOA, we also created propensity score-matched cohorts (16 EOA and 16 LOA). CD14 expression and its association with pain was estimated in LOA and EOA before and after propensity matching. We performed flow cytometry on tissues from the 16 patients, with 8 from each group, to assess for CD14+ subsets in the cells. The CD14 expression in EOA was higher than that in LOA both before and after propensity matching. The proportion of CD14high subsets in EOA was higher than that in LOA. The CD14 expression was associated with pain in EOA before matching. However, no difference was observed between the pain and CD14 expression after matching in EOA. The increased CD14 expression and the proportion of CD14high subsets may be important features associated with hip EOA pathology. To accurately compare early and late OA, the analysis of a propensity score-matched cohort is necessary.  相似文献   
52.
Summary Polyesters were modified by introducing small amounts of sodium sulfonate groups as hydrophilic groups in their backbones. Stable aqueous dispersions of the polyesters could be obtained by using 2-butoxyethanol (BEA) as a cosolvent. To clarify the role of the cosolvent, they were separated into two layers, polymer and supernatant layers, byultracentrifugation. Cosolvent contents were found to be different in the former and latter layers; i.e., the contents of BEA in the former layer are low in the case of crystalline polyesters and high in the case of noncrystalline ones. Characteristics of the dispersions such as viscosity are strongly affected by the content of the cosolvent.  相似文献   
53.
A phosphate glass fiber is fabricated by continuous drawing using a quartz double crucible. The raw materials for core and cladding glass are prepared at almost 100-percent efficiency by a liquid-phase process using ultra-high-purity chloride solutions. The transmission losses of the fiber are 2.5 dB/km at 1.1μm wavelength and 5.8 dB/km at 0.85 μm. The numerical aperture of the fiber is 0.31, and the breaking stress at 50-percent failure on the Weilbull plots is 3.5 kg for a 150-μm outside diameter. The phosphate glass is sufficiently water-resistant for practical use. Costs are less than 4 cents/m when phosphate glass fiber is produced continuously in quantities greater than 105km per year. This is approximately half the estimated cost of doped silica fiber.  相似文献   
54.
To improve the interaction between syndiotactic polypropylene (SPP) and fibrous cellulose (FC), the effects of the addition of maleated polypropylene (MAPP) and FC surface modification with 3‐aminopropyltriethoxysilane (APTES) on SPP/FC composites were studied with respect to the morphology and the tensile properties. The addition of MAPP brought about an improvement in the interfacial adhesion between SPP and FC according to scanning electron microscopy observations and tensile testing. This improvement was, however, less effective than the improvement in the interfacial adhesion between isotactic polypropylene (IPP) and FC. SPP and MAPP partially or microscopically phase‐separated because of the IPP‐like polymer chain structure of MAPP. With respect to the compatibility between SPP and FC, FC surface modification with APTES was more suitable. The increase in Young's modulus was remarkable in the SPP/silanized FC composite with APTES. The tensile strength of the SPP/silanized FC composite with APTES was, however, considerably lower than that of the SPP/FC/MAPP composite. These results suggest that interfacial improvement between SPP and FC requires a compatibilizer or a surface modifier with a suitable primary structure. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2009  相似文献   
55.
依据美国开发的BEES软件,选择张家港当地某一栋具体的多层住宅建筑(6层,每层大约750 m2)进行了生命周期评价.把建筑的全生命周期范围确定为建材准备阶段(包括原材科开采、运输、原材料加工等)、建造阶段、运行阶段(运行70年)、拆毁阶段和建筑垃圾处理阶段.依据确定的范围进行了清单分析.根据建筑的结构形式,计算得到各种建材的需求量和建造、运行、拆毁、建筑垃圾处理时的各种输入输出,以统一的功能单位(一栋建筑)合并各种输入输出数据,得到总的数据清单.采用BEES分类表征方法进行影响评价.根据我国的具体情况确定环境影响因子和类别(酸雨、全球变暖、资源枯竭等),将不同的环境影响因子分配到一个或多个环境影响类别中,再根据具体情况确定各指标的权重系数进行加权,得到综合的评价结果.找出了建筑物全生命周期阶段中产生环境影响最大的阶段,即运行阶段.  相似文献   
56.
In contrast to the conventional transformation of Bacillus subtilis using purified DNA, those using DNA in lysed protoplasts have a high transformation efficiency and enable whole-genome transfer into competent B. subtilis [Akamatsu, T. and Taguchi, H., Biosci. Biotechnol. Biochem., 65, 823-829 (2001)]. Here, we examined the length of incorporated continuous DNA by analyzing the cotransfer ratio with selected and unselected markers, on the basis of a new experimental design. The cotransfer ratio of a selected marker with an unselected marker on the opposite side of the genetic map of the B. subtilis chromosome was about 5.6% and could be interpreted as congression (double transformation) ratio. In the wild-type strain, the cotransfer ratio of cysA (113 kb position on 4215 kb of B. subtilis chromosome) with metC (1384 kb) and leuB (2891 kb) was 0.77%, twice the value (5.6% x 5.6%=0.31%) calculated from the congression ratio. Moreover, in a genetic background, the cotransfer ratios of metC with cysA and leuB, and metC with cysA and arg1 (3012 kb) were 2.7% and 7.2%, respectively. These results strongly suggest that the length of continuous DNA incorporated into B. subtilis is most probably greater than 1271 kb. When the DNA from the protoplast lysate was fragmented by mixing, the cotransfer ratios of arg1 with metC, and arg1 with metC and trpC (2374 kb) were 2.8% and 0.16%, respectively. A high cotransfer ratio (2.7-7.2%) could not, therefore, be obtained using the fragmented DNA. Based on these observations, we propose a working hypothesis on the mechanism of the transformation of competent B. subtilis by DNA in protoplast lysates (LP transformation).  相似文献   
57.
The feasibility of a method to monitor biofilm development non-destructively in a microfluidic device was addressed. Here, we report that biofilm growth could be non-destructively monitored by an image analysis technique based on modification of confocal reflection microscopy.  相似文献   
58.
The role of the competence protein ComEA in DNA uptake during transformation of competent Bacillus subtilis was analyzed by lysed-protoplast transformation (LP transformation). A comEA deletion mutant was constructed by a fusion polymerase chain reaction. Transformants of the mutant were obtained by LP transformation at a frequency of 1.1 × 10(2) transformants per μg DNA, representing a low relative efficiency of transformation [RET (mutant/wild type)] of 2.7 × 10(-6). This implied an important role of the protein during DNA uptake. When analyzing LP transformation of comEA with a plasmid (5.7 kb), a similar RET (mutant/wild type) of 5.6 × 10(-5) was obtained. Following addition of DNA into the comEA mutant culture, the number of transformants increased at a rate of 0.5 transformants/min, which was very low compared with the wild-type (6.9×10(4) transformants/min). However, even in the comEA mutant, DNA uptake began immediately after addition of DNA. Using co-transformation analysis of the comEA mutant, short linkages at distances of 2-156 kb could be detected, but not long linkages at distances of 671-1662 kb. Taken together, the results indicate that ComEA plays an important role in the transfer of transforming DNA into the DNA channel and in controlling the rate of DNA uptake.  相似文献   
59.
Recently, humanized animals whereby a part of the animal is biologically engineered using human genes or cells have been utilized to overcome interspecific differences. Herein, we analyzed the detail of the differentiation states of various human leukocyte subpopulations in humanized mouse and evaluated comprehensively the similarity of the leukocyte lineage between humanized mice and humans. Humanized mice were established by transplanting human CD34(+) cord blood cells into irradiated severely immunodeficient NOD/Shi-scid/IL2Rγ(null) (NOG) mice, and the phenotypes of human cells contained in bone marrow, thymus, spleen and peripheral blood from the mice were analyzed at monthly intervals until 4 months after cell transplantation. The analysis revealed that transplanted human hematopoietic stem cells via the caudal vein homed and engrafted themselves successfully at the mouse bone marrow. Subsequently, the differentiated leukocytes migrated to the various tissues. Almost all of the leukocytes within the thymus were human cells. Furthermore, analysis of the differentiation states of human leukocytes in various tissues and organs indicated that it is highly likely that the human-like leukocyte lineage can be developed in mice.  相似文献   
60.
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